Knockdown piano



C. F. STEIN May 2, 1950 KNOCKDOWN PIANO 3 Sheets-Sheet 1 5 OriginalFiled Dec. 21, 1946 INVENTOR. Charlesfi-ederz'c/b5m May 2, 1950 c. F.STEIN 2,505,805

KNOCKDOWN PIANO Original Filed Dec. 21, 1946 5 Sheebs-Sheet 2 IN VENTOR.

C. F. STEIN May 2, 1950 KNOCKDOWN PIANO 5 Sheets-Sheet 3 Original FiledDec. 21, 1946 mmvm. Garlkz rederz'a Siam Patented May 2, 1956 KNOCKDOWNPIANO Charles Frederick Stein, La Grange, Ill., assignor to Pratt, Readand Company, Inc., Ivoryton, Conn., a corporation of ConnecticutOriginal application December 21, 1946, Serial No. 717,678. Divided andthis application February 20, 1948, Serial No. 9,785

4 Claims.

This invention relates in general to pianos and more particularly to apiano structure including a, plurality of pro-assemblies which lendthemselves to high speed production methods and which are so constructedthat manufacture, shipping and storage of a high quality piano is madeeasier. This application is a, division of my application Serial No.717,678, filed December 21, 1946.

In the prior art it has been the general practice to manufacture pianoson an individually customized basis. This has been due primarily to thenature of prior art piano construction and due to the difficulty ofproducing, in such construction, a piano of the desired quality andperformance. Although various attempts have been made to speed up pianomanufacture and to apply high speed production assembly line methodsthereto, due to the requirement of hand fitting a great many parts ofthe piano, these methods have still resulted in pianos which areconsiderably different and in which the tone and performance varydepending upon the individuals who worked upon them.

Another reason why high speed manufacturing methods have not beensatisfactory for the manufacture of pianos is that in most commercialpiano structures, the piano casing is used for assembling many of theparts of the piano into a complete structure. For this reason specialcare must be taken of the piano casing during manufacture, assembly andadjustment of the piano, to prevent damage thereto. Even when takingsuch precautions, it is necessary that the casing be refinished aftermanufacture of the piano has been completed. The practice of forming thepiano case and operating structure into one complete unit has alsocomplicated shipment and storage of pianos because of the great weightand bulk of the completed piano structure. Piano construction in whichthe operating structure and casing are made in one composite unit issubject to another defect, that is, that the piano operating mechanismhas a relatively long life and the casing becomes out of style while thepiano is still in good condition. As the casing is used to support theoperating structure, it is very diflicult to remove the same and apply anew casing to thereby improve the appearance of the piano.

- Prior commercial piano constructions are also objectionable in thatthe completed piano is very heavy and hard to handle. This is caused bythe fact that in order to provide means sufiiciently rugged forstretching the strings of the piano, a

metal string plate together with a massive wooden back structure havebeen required. As the easing is used to support this back structure andalso the various operatin parts of the piano, it has had to beconstructed in a very rugged manner further increasing the weight of thepiano.

My Patent No. 2,431,350 and my copending applications, Serial Nos.585,053 and 643,713, are directed to knock down piano-structures whichovercome some of the above mentioned difficulties with reference topiano construction. The structure disclosed in this application includesimprovements and further features not disclosed in the aboveapplications.

It is an object of this invention, therefore, to provide a new andimproved knock down type piano in which the operating structure of thepiano and the case therefor are independent and can be easily assembledand disassembled.

A further object of this invention is to provide a piano having anoperating structure which is independent of casing therefor, and inwhich the operating structure is arranged so that a minimum amount ofspace is required for shipping and storing the same.

A still further object of this invention is to provide a piano havin aself-supporting operating structure and a case composed of a pluralityof parts which are assembled together as the case is applied to theoperating structure.

A feature of this invention is the provision of a single metal framemember for a piano on which all the operating components of the pianoare mounted and which is self-supporting to provide a, structure whichcan be completely adjusted and assembled without the use of the pianocasing.

A further feature of this invention is the provision of a pianooperating structure having a horizontal string chassis with bracketsremovably mounted thereon and a piano keybed pivotally secured to thebrackets so that the keybed can be moved from a normal position forplaying the piano to a position parallel with and adjacent the stringchassis so that a minimum amount of space is required for shipping andstorin the operating structure.

Further objects, features and advantages will be apparent from aconsideration of the following description taken in connection with theaccompanying drawings in which:

Fig. 1 is an exploded view showing the operating structure and removablecasing in accordance with this invention;

Fig. 2 is an exploded view of the back portion of the piano;

"toprotect the-piano action and the keys. movable supporting foot isprovided on the frame Fig.3 is a rear view of the back portion inassembled form;

Fig. 4 is a cross-sectional view of the back portion;

Fig. 5 illustrates the two positions of the keyboard; and

Fig. 6 shows a portion of the keyboard and mounting therefor.

In practicing my invention I provide a low upright piano having a backportion including a single frame member with a sounding board andstrings secured thereto. The frame member includes means for securingthe piano action thereto and brackets which "are-removably secured tothe frame member for supporting the keyboard of the piano. The keyboardis pivotally mounted on the brackets so that it may be positioned in thenormal operating position with respect to the piano action or pivoted toa position parallel to the frame member and adjacent the piano action tothereby provide a piano structure which may be shipped and stored in aminimum of space and inwhich thekeyboard tends A reso that the operatingstructuremay be held in "an upright position thereby. A casing isprovidedfor the piano including a plurality of members which areassembled as they are attached "to the operatingstructure of the piano.visions are included on the frame member for "attaching the casingthereto.

'Pro- Referring now more particularly to Fig. 1, there is'shown a pianooperating structure If] includ- -ing-a-back'portion A piano action l2and keyboard i3 are secured to the back portion, the

keyboard being supported by brackets I4. A supporting'foot I5 is alsosecured to the back structure for a purpose to be described hereinafter.-"Members adapted to form a casing are provided including sides 16, topmember shelf I8, music These various members are adapted to be operatingstructure. v

As is shown in Fig. 1, the piano'backiportion II "has openings thereinadapted to receive "dowels 3| on the sides l6 of the case to therebyposition thesides with respect to the operating structure. Registeringhinge-like portions 32 and 33 are provided on the frame and sidesrespectively for-securing'the sides tothe frame, pins "34 being providedto connect the hinge portions to thereby form simple and effectivesecurin means. After thesides have been secured'to the operatingstructure, the legs 25 are secured to the keybed I3 by screws or othersecuring means. projections 35 being provided in the legs to fit inopenings 36 in the keybed for positioning the legs with respect thereto.The toe rail 23 is then secured to the side members I6 with the channelmembers 31 thereon being positioned about projecting portions 38 on thesides and pins 39 bein positioned in openings in the members 31 and 38to hold the toe rail securely to the side member. Thereafter the bottompanel 24 may be secured in place with respect to the toe rail 23 andsides I6 by any suitable securing means, this member being removable inthe usual piano construction.

The key blocks 2| and the key slip 22 may now be set in place,supporting members 40 being provided on the sides of the'casing |6towhich these'members may be secured by screws or other securing means.The key blocks 2| include reor modern designs.

portions 45 adapted to cooperate with similar portions 4t on the frameH, the hinge portions being connected by pins 41 forming a hingedconnection for the top panel.

Itis obvious that the various parts of the case described above can beof such configuration that the assembled case will be of any desireddesigns, suchasthe various 18th century designs As cases of the variousdesigns may be applied to the same operating structure, it will bepossible for the owner of a piano to have his piano restyled by changingthe case thereof, without'removing the piano "fromhis home. Also, salesagencies can changethe cases of pianos to suit the desire of thepurchaser and thus reduce the number of'pianos which they must keep instock.

Reference is now made to Figs. 2, 3 and; in which the details of theback'port-ionof the operating structure are illustrated. 'The backportion includes a frame member 50 which is the sole supporting memberforthe entire operating structure for the piano. As indicated in Figs. 2and 4 the'frame includes a peripheral flange portion"5| and a centralweb portion 52 having a plurality of reinforcingribs 53 thereon andopenings 54 therein. The reinforcing ribs 53 are so positioned tostrengthen the frame'at the points where the tension of thepiano-strings cause the greatest stresses therein. A cross-rib 55 isprovided across the back of the framemember 50 forming a narrow upperrecess and a relatively large rectangular lower recess. A'pin block 56is positioned in the upper recess and a sounding board 51 is supportedin the lower recess. Openings 58 are provided in the webportionat theupper recess through which pins '59 extend into the pinblock 56 forsupporting the piano strings 60. Projections 6| are provided on certainof the reinforcing ribs 0n the frame'for supporting the other ends ofthe'strin'gs.

Thesounding-board 5'! includes'a relatively thin vibrating member 62having a surrounding frame portion 53 which-fits into the recess betweenthe cross-rib 55 and the peripheralflan'ge on the bottom andsides of theframe member. The sounding board is held in position by screws 64 whichare threaded into openings 65 in the web'portion 52 adjacent theperiphery thereof. Ribs-66 are provided on the backside of the soundingboard for stiffening the same and bridges 67 and 68 are provided on thefront-side in such a manner that they extend through openings 54 in theweb portion of the frame to contact the strings 60. Fig. 4 showsacross-sectional View of the frame member 50 with the pins '59, strings60 and sounding boardtl in place. Fig. 2 shows the manner in which thebridges 61" and 68 on the sounding board project'throughthe openings 54in the web portion.

As previously stated, the frame'me'mber'ifl of the back portion N formsthe support for the entire operating structure of the piano. Figs. 1 and5 illustrate the operating'str'ucture assembled on the frame member 50.As shown in the drawings, the frame 50 has a removable foot l5 securedthereto which is used to support the back portion of the piano in thenormal upright position. A projection 19 is provided on one of thereinforcing ribs 53 of the frame member having an opening H therein inwhich the foot is removably positioned. The foot is bent and may beplaced in the opening H at different angles so that the frame member 59may be tilted more or less (Fig. 5). A rubber tip 12 is provided on thefoot to provide a secure contact with the supporting surface. The footis adapted to hold the back portion, or the entire operating structureof the piano in the normal upright position while other supporting meansare secured thereto.

The piano action l2, which is provided as a preassembled unit, includesa plurality of supporting brackets 86 adapted to support the action onthe frame 50. Integral projections 89 are provided on the reinforcingribs 53 of the frame (Fig. 2) for supporting a horizontal bar 8! whichis provided for supporting the piano action in operative position withrespect to the strings. Forwardly extending projections 83 and pins 85which project upwardly are provided on the horizontal bar 8|. Thebottoms of the action brackets 86 include recesses adapted to fit overthe pins 85 to thereby mount the action on the bar 8|. The top portionsof the brackets 86 are supported on the web portion 52 of the frame 50by pins 81. Accordingly, it is seen that the action is supportedentirely on the frame member 59 and may be connected thereto or removedtherefrom as a unit after having first been preassembled. It is to benoted that the action fits closely to the web portion 52 and a portionthereof is within the space defined by the flange 5| of the frame. Thisprovides an operating structure of minimum depth.

In Figs. 5 and 6, there is illustrated the manner in which the keyboardI3 is supported on the frame member 50. The keyboard includes a keybed 93 on which the piano keys 95 are supported in a manner well known in theart. Brackets M are removably secured to the flange 5| of the framemember by screws 90, the brackets having portions 9| which abut theflange to thereby make a very rigid connection. The brackets [4 includeU-shaped trunnions 92 On the inside of the forwardly extending portionsthereof. Pins 93 are provided on the keyboard l3 positioned to engagethe trunnions 92 to thereby pivotally support the keyboard on thebrackets. This is clearly illustrated in Fig. 6. The keyboard may thusbe pivoted from a vertical position as shown in solid lines in Fig. 5 toa horizontal position shown in dotted lines in Fig. 5. In the verticalposition the operating structure of the piano may be stored or shippedin a relatively small space with the keybed 94 tending to protect thekeys 95 and the action l2. In the horizontal position, the keybed andkeys are in the normal playing condition with the capstan screws 96 atthe back end of the keys engaging the whips 91 of the piano action. Itis to be understood that the particular action disclosed and thecooperation between the keys and action is merely illustrative and othertypes of actions might be used in the same arrangement.

Means are provided for locking the keyboard in the two positions,comprising bolts 98 on the keyboard registering with openings 99 on thebracket l4. Additional bolts may be positioned in the keybedintermediate the ends thereof registering with openings in theprojections 83.

Wing nuts |0l are provided on the bolts for securely supporting thekeyboard in the horizontal playing position. When it is desired to pivotthe keyboard, the nuts IOI are removed and the keyboard pivoted in thetrunnions 92 to the vertical position. The trunnions 92 and the pins 93on the keyboard have openings therein which register when the keybed isin the vertical position. Pins I92 are provided which may be positionedin the openings to lock the keyboard in the vertical position. Thisarrangement is clearly shown in Fig. 5.

In manufacturing a piano in accordance with the invention, the backportion is first assembled with the pin block 56 and sounding board 51being secured to the frame 50 and the strings 60 strung thereon.Thereafter the foot I5 is secured in place on the frame and the bracketsM for supporting the keybed are applied. With the back portion held inupright position the piano action and keyboard are applied and the pianois com pletely regulated. It is apparent that a completely playablepiano is thus provided which does not include any parts of the pianocase. If it is now desired to ship or store the piano, the keyboard maybe pivoted to the vertical position and the foot [5 removed to therebypermit storing the operating structure in a minimum of space. When it isdesired to assemble the operating structure and case as a completepiano, the operating structure is again supported in the uprightposition by the foot IS, the keyboard is pivoted to the normalhorizontal position, and the case is then applied thereto as previouslydescribed. It is to be pointed out that after the legs 25 of the pianocase are secured to the keyboard, the foot l5 can be removed and bottompanel 24 put in place.

It is seen from the foregoing that in accordance with the invention astructure is provided wherein a piano may be assembled from a pluralityof preassembled units each of which is adapted for production linemanufacturing methods. The back portion is formed with a single framemember which replaces the usual string plate and wooden back structure,and as this frame member may be cast as a single member, the manufacturethereof is simplified to a large extent as compared with formerstructures. The use of the frame member of the back portion as the solesupporting member of the operating structure of the piano makes itpossible to completely assemble the operating structure before applyinga case thereto for styling the piano. The provision of the removablefoot on the frame member facilitates handling of the operating structureduring the various manufacturing and assembling processes. The pivotedkeyboard support results in an operating structure which requires lessspace for shipping and storage thereof and in general permits theshipping and storage of two pianos in the space previously required forone.

The case for the piano disclosed, which is made of a plurality of partswhich are assembled as the case is applied to the operating structure,permits very easy and fast changing of cases on an operating structure.This not only has the advantage of eliminating damage to the case duringthe manufacture of the operating structure but also results in therequirement of less shipping and storage space as the operatingstructure and various components of the case can be placed in much lessspace than is required for the completely assembled piano and case. Theprovision of interchangeable cases has the further advantage ofpermitting theuser of a piano to restyle a piano to conform with otherdecorations in his home and also permits "selling agencies 'to furnishthe cases desired by a particular purchaser without having a greatnumber of pianos in stock.

It 'is, therefore, seen that I have provided a piano structure in whichthe various components are 'sodesigned that assembly and regulation ofthe operating parts ar'every easily accomplished. Ifhe structure is suchthat a minimum amount of shipping and storage space is required and thatthe complete unit can be assembled very rapidly by relatively unskilledworkmen. "Ifhe regulation of the piano is not affected by the assemblyof the operating structure with respect to the case as the piano iscomplete and entirely playable without the case. I

Although I have described certain einbodinients of the piano structurein accordance with the invention, it is obvious that variouschanges canbe made therein without departing from the intended scope of theinvention as defined in the appended claims.

"1. Apiano operating unit adapted for use with case ii-leans, saidoperating unit being playable an'd'en'tirely self-supporting withouthaving case means therewith and including in combination a unitarystring chassis "having a single flanged frame, a sounding board,strings, and means for supporting said sounding board and strings onsaid frame in the space'defined by said fiang'es, a piano action inoperative relation with said strings, means for supporting said pianoaction on said string chassis, bracket means, means for supporting saidbracket means "on said string chassis, a playing portion including pianokeys, and means for pivotally supporting said playing portion on saidbracket means so that said playing portion is movablefrom'ahorizontal'position in which the keys are inposition'tooperate'said pianoaction to a vertical positioninWliich'theplaying portion is adjacent said piano action to thereby form a compactunit with said "playing unit bein'g positioned. to 'prote'ctsaid action.

'2. A piano operating unit adapted for use with case means,said'operating unit being playable and entirely self supporting withouthaving a case means therewith and'comprising a string chassis includinga single flanged metal framememb'er,

strings, a sounding board and means for supporting said strings andsounding board on said frame member in the space defined by said:flanges, a playing 'portion'including key support :r'neans a'nd'keymeans thereon,bracket means,

means for mounting said. bracket'means on'said :frame member out ofcontact 'with'the strings, means pivotally mounting said playing portionon said bracket means, and means secured to said frame member forsupporting said "operatingunit independently of a case means, saidplaying portion extending perpendicular t'o's'aid string chassis when inplaying position and being pivotable to aposition parallel'to'saidstring chassis to permit storage or transportation thereof inarelatively small space.

. 3. A piano operating unit adapted for use with case means, saidoperating unit comprising a back portion including a frame, strings anda sounding board, a piano action in operating positi'on with respect tosaid strings, means for mounting said piano action on said frame,bracket means, means for securing said bracket means to said frame, aplaying portion including piano keys thereon, means pivotally mountingsaid playing portion on said bracket means, supporting "means'remova'bly secured to said frame, said playing portion and saidsupporting means having operating positions in which said keys are innormal operating position with respect to said action and saidsupporting means supports said operating unit to provide a completeplayable unit, and non-operatingpositions inwhic'h said playing portionis pivoted toward said back portion and said supportingv means isremoved so that said operating unit forms a compact assembly.

4. A piano operating unit adapted for use with case means, saidoperating unit comprisinga back portion including a single frame memberwith strings and a sounding board thereon, piano action means inoperating position with respect to said strings, means for removablymounting said piano action means'on said frame, bracket means, means forremovably securing said bracket means to said frame member, a'playingportion having key support means and key means thereon, means pivotallymounting said playing portion on said bracket means, and supportingmeans removably secured to said frame, said playing portion and saidsupporting means having a first position in which said "key means are innormal operating position with respect to said action means and saidsupporting means supports said operating unit so that it is completelyplayable and entirely self supporting and a second position in whichsaid. playing portion is pivoted toward said back portion and saidsupporting means is removed so that saidoperating unit forms a'compactassembly which can be housed in a minimum amount of space.

CHARLES FREDERICK STEIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

Great Britain Sept. 10, 1925

